Energy Bands and the Soft-X-Ray Absorption in Si

The contribution of transitions from the $L$ shell to the imaginary part of the dielectric constant of silicon has been calculated including one-electron matrix elements. The inclusion of one-electron matrix elements does not resolve the discrepancy found between conduction-band density of states and soft-x-ray spectra. It is pointed out that, contrary to the claim of Kunz, the soft-x-ray data do not tell us the order of the zone-center levels in Si.